Pyeloectasia in children

Pyeloectasia is defined when the renal pelvis, the cavities that collect urine from the kidney calyxes, are found to be abnormally enlarged. Pyeloectasia in children is mostly congenital and does not always pose any health risks. Surgical treatment is relatively rare, as in many cases the problem goes away as the baby's organs mature.

If the calyxes are also dilated against the background of pelvic dilatation, the diagnosis of pyelocalicectasia or hydronephrotic renal transformation is made. If the ureter is also dilated against the background of pelvic dilatation, this disorder is called ureteropieloectasia (other possible names are megoureter, ureterohydronephrosis). [1], [2]

Epidemiology

Pyeloectasia in children is usually secondary - that is, the disorder occurs as a result of concomitant pathological processes that cause stasis and backflow of urine. The problem is detected most often in newborn babies and toddlers, sometimes in the fetus at the intrauterine stage of development.

According to statistics, boys are about six times more likely to suffer from pyeloectasia than girls.

The code of the disease according to the International Classification of Diseases of the Tenth Revision is Q62. Other possible names of the pathology: calycopieloectasia, hydrocalicosis, calycoectasia, pyelocalicoectasia.

The prevalence of pyeloectasia in children according to prenatal ultrasound diagnostics is 2.5 cases per 1 thousand. All newborns with prenatally detected pyeloectasia are dynamically monitored: obstructive uropathies are predominantly found among the detected urologic pathologies.

In most situations, the pediatric course of the disease is favorable. In about a quarter of children, the problem resolves itself by the time of the first ultrasound. In another quarter, the problem disappears on its own during the first year of life. Surgical correction is required in about 8% of cases. [3]

Causes of the pyeloectasia in children

Doctors talk about the variety of causes that can entail the development of pyeloectasia in children. If we take into account that the first and main factor in the appearance of enlargement is the stagnation of urinary fluid in the lobules and problems with its outflow, then the causes of pathology can become such diseases and conditions:

• anatomical defects of the ureteropelvic-lochanic system;
• excessive pressure on the ureters - for example, as a result of tumors, enlarged internal organs or blood vessels;
• muscle weakening;
• malformed or twisted ureters;
• infrequent urinary urges;
• traumatic kidney injuries;
• Infectious-inflammatory diseases (nephritis and pyelonephritis), autoimmune processes (glomerulonephritis).

Sometimes pyeloectasia in children is detected at the intrauterine stage: such a disorder can be hereditary, or provoked by various pathologies or intoxications during pregnancy. Thus, hereditary pyeloectasia in the fetus can be detected by ultrasound as early as 16-20 weeks of gestation.

Pyeloectasia in older children is formed as a consequence of inflammatory processes affecting the urogenital apparatus, or when the ureters are blocked - for example, when tamponed with mucous or purulent plugs, particles of necrotized tissue. If the child suffers from urolithiasis, the ureters may be blocked by sand or stones.

Infants sometimes have a condition called neurogenic bladder, in which there is constant spastic compression of the urinary organs.

Experts note that the most common root cause of pyeloectasia in children is the creation of urinary backflow, when urine rushes backward from the bladder to the kidneys. A normal urinary system involves a valve system that prevents backflow of fluid. If the valve system for some reason does not work, then the urine against the background of contractile activity of the bladder is directed not down, but up - along the ureter to the pelvis. Such a violation is called vesico-ureteral (vesico-ureteral) reflux. It is caused mainly by congenital defects in the development of the uretero-vesicoureteral junction. With improper development of the intramural duct, the valve system does not function fully, as a result of which urine is thrown in the opposite direction. Vesico-ureteral reflux is dangerous for the development of infectious complications of the urinary tract and their frequent recurrence. [4]

Risk factors

The kidneys are organs that play a vital role in maintaining a stable internal environment. During the intrauterine development of the fetus, the kidneys start their work as early as 3-4 weeks, and urine excretion is noted from the ninth week. Immediately after the appearance of the child in the world, the urinary system becomes the main mechanism of excretion of metabolic products from the body. At the same time, the share of defects in the development of the urinary system is up to 50% of all congenital anomalies in children.

Through the kidneys, blood is pumped repeatedly throughout the day. The organs are actively involved in the removal of metabolites, toxins and foreign components from the body, in maintaining water-electrolyte and acid balance, as well as immunity.

Pyeloectasia in children can be congenital, hereditary, or acquired.

Special attention should be paid to the health of pregnant women, starting from the very moment of conception. Improperly formed urinary system in the future baby entails a violation of renal function and the start of pathological processes. Developmental disorders of the urinary apparatus often occur during the newborn period, as well as in infancy, preschool and early school age, which is associated with the impact of various damaging factors.

The development of pyeloectasia in children can be associated with various viral pathologies. It is important to conduct timely vaccination, detect and treat such diseases. [5]

In recent years, the number of renal problems caused by unfavorable environmental factors, exposure to heavy metals, radionuclides, chemical agents has increased. Children who live in ecologically polluted regions should take preventive courses - in particular, increase the drinking regime, add more plant foods to the diet, additionally take vitamins and antioxidants (as recommended by the pediatrician).

The presence of children with weakened immunity, dysbacteriosis suggests appropriate therapy, since such conditions often provoke the appearance of various pathological processes, including diseases of the urinary apparatus.

Most cases of pyeloectasia are found in children who were born to parents who use alcohol or drugs. [6]

Pathogenesis

Congenital pyeloectasia in children, either has a genetic origin, or appears due to unfavorable effects on the maternal body and fetus during gestation.

The renal pelvic cavities are cavities that store urinary fluid from the renal calyces. From the pelvis, urine flows into the ureters and then into the bladder.

The most significant factor in the development of pyeloectasis is improper urine flow from the renal pelvis, or backward flow of urine - ureteropelvic reflux. If the urinary system is healthy, this backflow is prevented by valves present at the area where the ureter enters the bladder. In people with reflux, the valve system malfunctions: when the bladder contracts, urinary fluid is directed upwards, rather than downwards, towards the kidneys.

Often the normal flow of urine is obstructed by spasm or narrowing of the ureter in the area where the ureter joins the pelvis, or in the area where the ureter enters the bladder. The problem may be related to abnormal or underdevelopment of the ureter, or to external compression of the ureter by adjacent structures or tumors. In some children, the violation is caused by the formation of a valve in the zone of transition of the pelvis to the ureter - we are talking about the so-called high ureteral outlet. Excessively high urethral pressure resulting from abnormal nerve innervation of the bladder (neurogenic bladder) or valve abnormalities in the urethra can also affect the urine flow from the renal pelvis.

Pyeloectasia in children is an indicator of an unfavorable state of the urinary system. Problems with urine flow can worsen, provoke compression and atrophy of renal structures, deterioration of organ function. In addition, the disorder is often associated with the development of pyelonephritis - an inflammatory process in the kidneys, which significantly worsens the condition and often leads to the formation of renal sclerosis. [7]

Symptoms of the pyeloectasia in children

In many children, pyeloectasia is detected accidentally during routine ultrasound examinations. With a mild course of the disorder, the first signs are observed only a few months or even years after birth, but often the problem disappears on its own, the symptomatology does not make itself known.

A pronounced enlargement of the pelvis, regardless of age, may be accompanied by these symptoms:

• kidney enlargement and associated visible abdominal enlargement;
• Urinary disorders, including painful urine output;
• positive Pasternatsky's symptom (appearance of painfulness when tapping in the area of kidney projection);
• signs of inflammation (detected by laboratory);
• initial symptoms of chronic renal failure (apathy, general weakness, thirst, bad taste in the mouth, memory impairment, sleep disorders, nausea, etc.).

There may be pyeloectasia of the left, right kidney in a child, which is practically not reflected in the overall clinical picture. An important role in the symptomatology plays only the intensity of the pathological process and the size of the enlargement, as well as the presence of concomitant diseases and complications. For example, it is possible to join the picture of urolithiasis (renal colic, lumbar pain), tumor processes in the kidneys (back pain, blood in the urine, etc.), chronic inflammatory process (signs of intoxication, urine turbidity, etc.).

Pyeloectasia of the left kidney in a child is somewhat less common than the right, which is due to the anatomo-physiological features of the urinary excretory apparatus.

If the pelvic dilatation becomes infected, the symptoms become intense and vivid:

• temperature rises to 38-40°C;
• you get chills;
• headache, possible dizziness;
• nausea appears, sometimes to the point of vomiting (without subsequent relief);
• loss of appetite;
• weakness, unmotivated fatigue, brokenness.

If the disease rapidly progresses, then the doctor can diagnose hydronephrosis, and with simultaneous enlargement of both the pelvis and the calyx, the probability of developing renal failure increases significantly.

The main difference between pathological enlargement of the pelvic ducts in an adult and a child is that pyeloectasia in children under a year of age is often traceless and asymptomatic. As for adult pyeloectasia, in this case, there is almost always a connection with other renal diseases, which causes a more severe course and constant progression of the disease with the development of complications. [8]

Criteria for pyeloectasia in children

Pyeloectasia is categorized according to a number of criteria:

• distribution and location;
• severity;
• time of appearance;
• the presence of concomitant pathologies.

The distribution of pyeloectasia allows us to distinguish such types of violation:

• dilated collecting system of the kidney on the left;
• dilation of the right renal pelvis;
• bilateral pyeloectasia.

According to the time of occurrence, congenital and acquired pyeloectasia are distinguished.

There is a classification according to the degree of pyeloectasia in children:

• mild degree of dilation (up to 7 mm inclusive, no symptoms, renal function is not impaired);
• Moderate pyeloectasia in a child (up to 10 mm dilation, symptomatology is weak, concomitant pathologic conditions are present);
• severe pyeloectasia (dilation is pronounced, urinary dysfunction is observed).

If the lobules are dilated by more than 10 mm, it is often said to develop hydronephrosis.

Mild slit pyeloectasia in children requires regular monitoring by urologists or nephrologists, and with moderate or severe degrees, medication is necessarily prescribed to prevent the development of severe complications.

There are unilateral (left or right kidney) and bilateral pyeloectasia in a child (affecting both kidneys). As it progresses, there are mild, moderate and severe variants of the course. [9]

Complications and consequences

Pyeloectasia in children, regardless of age, can provoke other renal pathologies, as well as disorders of the entire genitourinary sphere. Congestion in the lobules can lead to the development of the following complications:

• Megaureter - abnormal dilation of the ureter due to increased pressure in the bladder;
• Ureterocele - narrowing of the ureteral orifice at the level of the bladder;
• Hydronephrosis - increasing enlargement of the renal pelvis with further atrophic changes in the parenchyma;
• urethral ectopia - pathologic changes in the urethra due to chronic disorder of urine flow;
• microlithiasis - accumulation of microliths - crystals, conglomerates of salt sediment in the kidneys;
• Chronic pyelonephritis is an inflammatory disease of the kidneys, which is accompanied by damage to the tubule system;
• Vesico-ureteral reflux - backflow of urine.

These pathological processes significantly complicate the already impaired renal function and often lead to the development of chronic renal failure. Acute forms of complications along with an active inflammatory response, the presence of infection in the urinary fluid contribute to the spread of infectious agents in the body, up to septic process.

It should be understood: not every case of pyeloectasia in children ends up with serious complications. In many cases, the pelvic dilation normalizes on its own after some time.

The probability of unfavorable consequences increases significantly if negative annual dynamics, changes in the structure of the pelvis, additional pathological symptoms appear during observation. All children with pyeloectasia should be registered with a nephrologist or urologist. [10]

Diagnostics of the pyeloectasia in children

If pyeloectasia in a child is not sharply expressed and is asymptomatic, then it is enough to systematically perform ultrasound studies, which are determinant in the diagnosis.

If an infectious-inflammatory process joins, or the degree of enlargement increases, then a complete instrumental diagnosis is performed, including radiologic studies, such as:

• cystography;
• intravenous (excretory) urography;
• radioisotope renal study.

These procedures help to determine the diagnosis, clarify the degree and root cause of abnormal urine flow, prescribe the correct in this situation therapeutic measures.

The echo signs of pyeloectasia in a child are enlargement of the kidney pelvis beyond normal:

• 31-32-week fetus - the pelvic cavity should not exceed 4-5 mm;
• 33-35-week fetus - dilation of no more than 6 mm;
• 35-37-week fetus - cavity no larger than 6.5-7 mm;
• newborn infant - up to 7 mm;
• 1-12-month-old baby - up to 7 mm;
• child 1 year and older - 7-10 mm.

These norms are not universally accepted and may differ according to different authors, so do not be guided only by the figures. All children are different, and even kidneys can be different sizes.

Tests in mild forms of pyeloectasia often have no deviations from the norm. In more complicated cases, urine examination reveals leukocyturia, proteinuria, bacteriuria - signs of inflammatory reaction. For urolithiasis and metabolic nephropathy is characterized by precipitation of salts in the urine.

In bilateral pyeloectasia, the doctor may recommend a blood test for creatinine and urea: elevated levels of these parameters indicate the development of renal failure.

If bacteriuria is present, the biomaterial is taken to identify the microflora and determine its sensitivity to antibiotics.

Differential diagnosis is performed between physiologic and pathologic forms of pyeloectasia. In this situation, the main task of the doctor is to determine the underlying cause of enlargement.

Treatment of the pyeloectasia in children

Therapeutic measures are not prescribed in all cases of this pathology in children. For example, physiologic renal pyeloectasia usually goes away on its own after about 7 months of age. With positive dynamics and a steady absence of symptoms and worsening, only control and supervision by specialists is necessary. In addition, often by one and a half years of age, the disorder is completely self-corrected, which is associated with the active growth of children.

A mild course of pyeloectasia requires systematic dynamic observation, without the use of urgent therapeutic measures. In all other cases, it is possible to prescribe both conservative and surgical interventions. The scheme of treatment of pyeloectasia in children is always individual, as it depends on such points as:

• the root cause of the pathology;
• the severity of its course, the presence of symptoms and signs of renal dysfunction;
• comorbidities;
• the age of the child.

In most cases, conservative treatment includes the prescription of such drugs:

• diuretics;
• antibacterial agents;
• anti-inflammatory drugs;
• circulatory activators;
• immunomodulators;
• litholytics;
• analgesics;
• multivitamins.

Dietary changes are mandatory. A low-protein and salt-free diet is recommended.

Surgery involves correction of the size of the pelvis. It is rarely performed on infants, only in cases of severe pathology. The practice of such interventions is possible:

• palliative intervention to restore renal function (epicystostomy, nephrostomy, ureteral catheterization, etc.);
• pelvic plasty;
• removal of stones and other obstructions from the pelvis, ureters, etc;
• partial kidney resection;
• nephrectomy (if irreversible changes in the organ and complete loss of its function are detected).

Surgical methods most often involve the use of laparoscopy, or transurethral procedures under general anesthesia. [11]

Prevention

There is no specific prevention of pyeloectasia in children. But it is possible to reduce the risks of developing this disorder at the stage of gestation. Expectant mothers should avoid the possible influence of unfavorable factors, control the general state of health. Doctors emphasize the following particularly important recommendations:

• improve a woman's nutrition during the entire period of planning and carrying a child, to ensure adequate intake of vitamins and micronutrients (special attention is paid to sufficient intake of iodine and folic acid);
• eliminate exposure to alcohol and tobacco products;
• eliminate the effects of teratogenic substances, including pesticides, heavy metals, certain medications, etc;
• Improve somatic health indicators (normalize weight, control blood sugar levels, take measures to prevent gestational diabetes);
• prevent the development of intrauterine infections;
• visit doctors regularly, monitor your own health and the course of your pregnancy.

It is important to provide the pregnant woman's body with an adequate amount of vitamin A. It is a fat-soluble growth factor that influences gene transcription. Vitamin A takes part in the formation of the skeletal system, supports the cells of the skin epithelium and eye mucous tissues, ensures the normal state and function of the respiratory, urinary, digestive apparatus. The embryo is not able to independently produce retinol, so the intake of the vitamin from the mother is extremely necessary. By the way, ethyl alcohol blocks retinaldehyde dehydrogenase during the formation of the embryo and thus damages various embryonic structures, causing malformations.

Progressive retinol deficiency entails dose-dependent shrinkage of the embryonic hindbrain, underdevelopment of the larynx, severe ataxia and blindness, and congenital kidney abnormalities.

However, not only a deficiency, but also an excess of vitamin A is dangerous for the fetus. Therefore, it is important not to engage in self-treatment and self-prophylaxis without prior consultation with doctors.

Pediatricians note these prevention highlights:

• early diagnosis of the kidney condition of the unborn baby;
• timely therapy of infectious pathologies;
• Avoiding contact with people who have viral illnesses;
• prevention of hypothermia;
• Special health monitoring of children with an aggravated history of hereditary kidney disease;
• adequate organization of diet, drinking and physical activity;
• Education of children in correct nutritional priorities (predominance of vegetable food, low salt, exclusion of unhealthy foods);
• timely vaccine prophylaxis.

Forecast

The prognosis of pyeloectasia in children cannot be unambiguous, since the outcome of the disorder depends on a number of factors, such as the cause of pelvic dilatation, the presence of other diseases and complications, the presence or absence of symptomatology.

If there are persistent renal dysfunctions, the child is prescribed appropriate therapy. If chronic renal failure develops, treatment becomes more complicated and a long-term complex therapeutic course is prescribed. In the terminal stage of renal failure, surgical assistance may be required.

When children with severe pyeloectasia are not treated, chronic renal failure often develops.

In general, pyeloectasia in children most often has a favorable course: the enlargement gradually disappears, the function of the organ does not suffer. But it is important to understand that in childhood there are several active stages of growth - this is six months, 6 years and puberty. During these periods, pyeloectasia can recur, although usually this, if it happens, then in a relatively mild form. Therefore, children, even those who have coped with the disorder, should be examined regularly.